posi fluid

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dondon
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posi fluid

Post by dondon » Thu Jan 11, 2018 10:46 pm

Is that 4 ounce bottle posi additive needed on a 8 3/4 mopar cone type posi or is it only needed for the clutch type posi?

Geoff2
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Re: posi fluid

Post by Geoff2 » Fri Jan 12, 2018 3:15 am

I have a GM axle that uses the cone style posi & it requires LSD additive. Don't see why Mopar would be different...

SupStk
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Re: posi fluid

Post by SupStk » Fri Jan 12, 2018 9:53 am

On a related topic, is the aditive required when using synthetic lube with a clutch type limited slip? Or is the synthetic a bad idea? The differential is a 9" Ford with Trac-loc.
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Re: posi fluid

Post by tresi » Fri Jan 12, 2018 4:39 pm

SupStk wrote:
Fri Jan 12, 2018 9:53 am
On a related topic, is the aditive required when using synthetic lube with a clutch type limited slip? Or is the synthetic a bad idea? The differential is a 9" Ford with Trac-loc.
I've heard not to use synthetic with a limited slip rear end but that might only be worth what you paid for it.

Geoff2
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Re: posi fluid

Post by Geoff2 » Sat Jan 13, 2018 4:46 am

I always buy rear axle oil that has the LSD additive as part of the oil. That way you know the two are compatible. I see no sense in buying 'straight' oil & adding 'something' to it when all the major companies make oils with the required LSD additive.
One of my diffs was noisy when coasting [ worn gears, no new replacements available ] . Tried two different brand oils to try & reduce the noise, no difference. Then I tried Redline 85/140 syn oil. Noise was almost eliminated, & I ONLY use Redline syn oil now in the axle.

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Re: posi fluid

Post by stealth » Mon Jan 15, 2018 2:04 pm

Geoff2 wrote:
Sat Jan 13, 2018 4:46 am
I always buy rear axle oil that has the LSD additive as part of the oil. That way you know the two are compatible. I see no sense in buying 'straight' oil & adding 'something' to it when all the major companies make oils with the required LSD additive.
One of my diffs was noisy when coasting [ worn gears, no new replacements available ] . Tried two different brand oils to try & reduce the noise, no difference. Then I tried Redline 85/140 syn oil. Noise was almost eliminated, & I ONLY use Redline syn oil now in the axle.
Agree...

Good to hear the redline worked well. Have to give it a try.
The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man.

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